Paul Gross, creator of the 2008 film Passchendaele, on the origins of his interest in World War I.

There’s a small lake in southern Alberta called Cowoki that is stocked with jackfish and yellow perch. One day I went fishing there with an old man. I was 16 and it was an auspicious day because he let me drive the boat for the first time.

As usual, I pestered him with questions about the war he had survived, the Great War. Irritating questions such as, “Did you kill Germans? Did you shoot the Hun?” Normally, he would deflect this with hilarious vignettes about life behind the front, but on this day he started talking.

After the Battle for Vimy Ridge he was part of a patrol mopping up through a ruined village when they encountered a machine-gun nest. The patrol and the gun exchanged fire for many hours until everyone in his patrol was dead or wounded except him, and the machine gun was quiet. He fixed his bayonet and charged the nest to discover one young German soldier still alive, blood seeping from his many wounds.

“He had these blue eyes, these watery blue eyes,” said the old man. The young German raised his hand, and said, “Kamerad.” The old man told me he looked at him for a second, then bayoneted him in the forehead. “I wasn’t angry, I wasn’t frightened — I just killed him,” he said.

The old man was my grandfather and his name was Michael Joseph Dunne. He was born in Ballyraggan, County Kildare, Ireland. His family emigrated to Canada, settling first in Cape Breton, eventually drifting west. It was in Calgary that my grandfather signed up — an act of whimsy, really, one that gripped almost one-tenth of our country’s population.

He fought for the duration of the war and was wounded three times, the last during the Battle of Amiens. That wound sent him home. Of this he would say only that he was “shot in the left side.” In fact, his medical records reveal that he was shot 15 times in the left side, most likely strafed by a machine gun. He was a tough man, my grandfather, tough in a way we can almost no longer imagine.

This Great War was the central event in his young life and the event he returned to as he neared death in a hallucinatory haze. He may have been in a hospital but in his mind he was in the trenches.

And he was trying to apologize. Over and over he was saying, “I’m sorry.” And I know, in my bones I know, he was trying to apologize to the boy he’d bayoneted.

From that fishing trip forward, I was gripped by the horrors of the Great War. Over time, my attention drifted from the large movements of great armies to the more intimate costs exacted from those millions of men and boys who left their homes and families to step inside the abattoir.

This obsession eventually found expression in a movie I made called Passchendaele, named after one of the more savage battles in a uniformly savage war. It was in the course of shooting the battlefield sequences that I realized I was making the movie in an attempt to understand my grandfather. I think I felt at least a whisper of what he endured and that whisper has given me a respect for those men and boys that cannot be compassed in words.

As amazing as my grandfather’s story is to me, it’s one that is repeated over and over in the almost 650,000 men and boys our nation shipped to the abattoir of World War I. Perspective: in today’s numbers, we’d have sent roughly three million men and women to war. Of those, one and a half million would have been wounded. And 300,000 would have been killed.

The scale of our young country’s wound is etched in stone in every cenotaph in every town and every village and all the cities of our nation. The next time you find yourself passing one, please stop. Get out of your car. Read the names. Imagine they were your children.

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